﻿/*
  KeePass Password Safe - The Open-Source Password Manager
  Copyright (C) 2003-2021 Dominik Reichl <dominik.reichl@t-online.de>

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Text;

using KeePassLib.Interfaces;

#if KeePassLibSD
using KeePassLibSD;
#endif

namespace KeePassLib.Collections
{
  public sealed class StringDictionaryEx : IDeepCloneable<StringDictionaryEx>,
      IEnumerable<KeyValuePair<string, string>>, IEquatable<StringDictionaryEx>
  {
    private SortedDictionary<string, string> m_d =
        new SortedDictionary<string, string>();

    // Non-null if and only if last mod. times should be remembered
    private Dictionary<string, DateTime> m_dLastMod = null;

    public int Count
    {
      get { return m_d.Count; }
    }

    public StringDictionaryEx()
    {
    }

    internal StringDictionaryEx(bool bRememberLastMod)
    {
      if (bRememberLastMod) m_dLastMod = new Dictionary<string, DateTime>();
    }

    IEnumerator IEnumerable.GetEnumerator()
    {
      return m_d.GetEnumerator();
    }

    public IEnumerator<KeyValuePair<string, string>> GetEnumerator()
    {
      return m_d.GetEnumerator();
    }

    public StringDictionaryEx CloneDeep()
    {
      StringDictionaryEx sdNew = new StringDictionaryEx();

      foreach (KeyValuePair<string, string> kvp in m_d)
        sdNew.m_d[kvp.Key] = kvp.Value;

      if (m_dLastMod != null)
        sdNew.m_dLastMod = new Dictionary<string, DateTime>(m_dLastMod);

      Debug.Assert(Equals(sdNew));
      return sdNew;
    }

    public bool Equals(StringDictionaryEx sdOther)
    {
      if (sdOther == null) { Debug.Assert(false); return false; }

      if (m_d.Count != sdOther.m_d.Count) return false;

      foreach (KeyValuePair<string, string> kvp in sdOther.m_d)
      {
        string str = Get(kvp.Key);
        if ((str == null) || (str != kvp.Value)) return false;
      }

      int cLastModT = ((m_dLastMod != null) ? m_dLastMod.Count : -1);
      int cLastModO = ((sdOther.m_dLastMod != null) ? sdOther.m_dLastMod.Count : -1);
      if (cLastModT != cLastModO) return false;

      if (m_dLastMod != null)
      {
        foreach (KeyValuePair<string, DateTime> kvp in sdOther.m_dLastMod)
        {
          DateTime? odt = GetLastModificationTime(kvp.Key);
          if (!odt.HasValue) return false;
          if (odt.Value != kvp.Value) return false;
        }
      }

      return true;
    }

    public string Get(string strName)
    {
      if (strName == null) { Debug.Assert(false); throw new ArgumentNullException("strName"); }

      string str;
      m_d.TryGetValue(strName, out str);
      return str;
    }

    internal DateTime? GetLastModificationTime(string strName)
    {
      if (strName == null) { Debug.Assert(false); throw new ArgumentNullException("strName"); }

      if (m_dLastMod == null) return null;

      DateTime dt;
      if (m_dLastMod.TryGetValue(strName, out dt)) return dt;
      return null;
    }

    public bool Exists(string strName)
    {
      if (strName == null) { Debug.Assert(false); throw new ArgumentNullException("strName"); }

      return m_d.ContainsKey(strName);
    }

    public void Set(string strName, string strValue)
    {
      if (strName == null) { Debug.Assert(false); throw new ArgumentNullException("strName"); }
      if (strValue == null) { Debug.Assert(false); throw new ArgumentNullException("strValue"); }

      m_d[strName] = strValue;

      if (m_dLastMod != null) m_dLastMod[strName] = DateTime.UtcNow;
    }

    internal void Set(string strName, string strValue, DateTime? odtLastMod)
    {
      if (strName == null) { Debug.Assert(false); throw new ArgumentNullException("strName"); }
      if (strValue == null) { Debug.Assert(false); throw new ArgumentNullException("strValue"); }

      m_d[strName] = strValue;

      if (m_dLastMod != null)
      {
        if (odtLastMod.HasValue) m_dLastMod[strName] = odtLastMod.Value;
        else m_dLastMod.Remove(strName);
      }
    }

    public bool Remove(string strName)
    {
      if (strName == null) { Debug.Assert(false); throw new ArgumentNullException("strName"); }

      if (m_dLastMod != null) m_dLastMod.Remove(strName);

      return m_d.Remove(strName);
    }
  }
}
